1. Field of the Invention
The present invention relates to a method of point to multipoint radio service, and more particularly to a data transmission by which a mobile telephone network subscriber can transmit data simultaneously to a plurality of public switched telephone network (PSTN) subscribers.
2. Description of the Related Art
Generally, an interworking function device (IWF) is used as an interface between a mobile communication network and other networks. Through the IWF, data from a subscriber of mobile communication network such as a digital mobile telephone network or personal communication network is transmitted to a PSTN subscriber which is a wire telephone network. FIG. 1 is a block diagram of a conventional mobile communication network interworking with the PSTN.
Referring to FIG. 1, a conventional mobile communication network interworking with the PSTN through the IWF includes a terminal equipment (TE) 1, a mobile terminal (MT) 2 connected to the terminal equipment, a base station (BS) 3 providing a wireless channel connection to the mobile terminal 2, a base station controller (BSC)/mobile switching center (MSC) 4, a IWF 5 connected to the BSC/MSC 4 performing an interworking function between the mobile communication network and other networks, a PSTN 10 interworking with the mobile communication network, a wire modem 11 connected to the PSTN, and a terminal 15 connected to the wire modem.
The TE 1 includes a mobile equipment such as a notebook computer and a typical communication emulator to enable data communication. The terminal 15 may be another TE including equipment such as a typical computer or facsimile machine.
The IWF 5 includes a first block 6 connected to the MSC for determining and releasing a wireless data communication path; a second block 7 provided with the traffic data path from the connection of the first block 6 to the MSC for performing data transmission/reception with the mobile terminal in an end-to-end manner using an upper protocol over a network hierarchy; a third block 8 also connected to the MSC for determining a link with the PSTN; and a fourth block 9 provided with the traffic data path to the wire modem 11 through a modem pool from the connection of the MSC to the third block for performing data transmission/reception with the wire modem 11.
In a typical mobile communication network interworking with the PSTN, the wireless data service for digital mobile and personal communication networks utilizing the IWF allows only a one-to-one communication when transmitting circuit data and facsimile data. Accordingly, when a mobile communication subscriber intends to transmit circuit data or facsimile data to a plurality of PSTN subscribers through a mobile terminal, the subscriber must repeatedly transmit the data to each PSTN subscribers one by one, which takes a significant amount of time.
Accordingly, an object of the present invention is to solve at least the problems and disadvantages of the related art.
An object of the present invention is to provide point to multipoint radio service which enables a mobile telephone network subscriber to simultaneously transmit data to a plurality of PSTN subscribers.
Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objects and advantages of the invention may be realized and attained as particularly pointed out in the appended claims.
To achieve the objects and in accordance with the purposes of the invention, as embodied and broadly described herein, a multiple uni-directional radio data service method includes originating a call simultaneously to a plurality of PSTN subscribers based upon inputs from a mobile telephone network subscriber; processing the call and allocating a plurality of modems in an interworking function device based upon the call; and determining traffic paths between the plurality of modems in an interworking function device and wire modems of the plurality of PSTN subscribers.
In the above method, the call may be originated by inputting an AT instruction; inputting a desired telephone number after the AT instruction; inputting a first specified sign after the telephone number to identify the inputted telephone number; inputting other telephone numbers by repeating the steps of inputting the telephone number and the first specified sign; and inputting a second specified sign to identify an input of a final telephone number.